I attended community college after high school in the Bay Area and then transferred over to San Jose State University's business school for a major in Business Administration with a concentration in MIS. This major required basic fundamentals of business courses, such as Finance, Accounting, Marketing, and MIS courses as well. It was a great major to be well-rounded in Business to understand other aspects outside of information systems as you are highly likely to collaborate with other groups in your future career in Technology.
I will say most people in my major ended up in Consulting (Deloitte/KPMG/EY etc). Similarly, I started my career in a consulting type role where I support software implementations. Some others who were more tech minded (keep in mind that it is a blend of business and tech, often times, people are not fully technical) went into game development, paired with computer science, etc.
I would urge to find out more about the career you'd be interested in and take courses which are interesting and geared towards that path.
It depends on the university you want to attend and the specialization. I attended the University of Houston and graduated with MIS degree. In this case, the program included both business and technical courses. Business courses focused on the business aspect such as management, statistics, marketing and economics. The technical classes had several paths that you can choose from, and there are a few classes that is MIS specific. General classes like Into to MIS, Advanced MIS, and intro to networking. An example on specialized classes would be transaction systems.
You can also examine some of the certifications that are related to MIS which I recommend doing. Some of the certification: ITIL, Microsoft certification, Project Management (not really MIS but it is complementary to the subject as MIS work is mostly project work), CIP (certified information management practitioner and others.
The best path I can suggest is to start the MIS curriculum and gage individual interests.
Hope this helped.
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